AIM 1- The Stroger/CORE ATU will continue to work collaboratively within the ATN structure to assist in the implementation of interventional studies that address HIV/AIDS among adolescents and young adults (ages 12-25) through primary, secondary, and tertiary prevention approaches. AIM 2 - The Stroger/CORE ATU's HIV experienced, multidisciplinary clinical staff will be responsible for ATN subject recruitment, retention, and safety in conjunction with our wide array of adolescent-specific services in our well established adolescent HIV care program. AIM 3 - The Stroger/CORE ATU will enroll and monitor subjects in a central managerial database, continuously monitor its managerial capacity for conducting research protocols and reporting on protocol implementation, data collection, and submission via continuous quality assurance of these capabilities by key personnel. The Stroger/CORE Center Adolescent Trials Unit (ATU) operates as part of the Division of Adolescent and Young Adult Medicine, Department of Pediatrics at Stroger Hospital (JSH) and has a comprehensive health care clinic, the Adolescent Medicine Program at CORE (AMaC), housed at the Ruth M. Rothstein CORE Center. JSH is the largest provider of comprehensive services for all youth in Chicago. The CORE Center is the largest free standing clinic dedicated to the treatment and research into HIV and other infectious disease in the U.S. CORE operates on principles of cultural competency, with specific clinics and resources dedicated to adolescents and adolescent-medicine trained physicians and nurse practitioners. The clinic currently has 223 HIV positive youth age 13 to 24 years old, in care. Our youth patients are culturally diverse: 83% African American, 11% Latino, 4% Caucasian and 3% Other. By gender, 74% are male, 23% are female and 3% are transgender. Our ATU's experience in implementing the Adolescent Trials Network (ATN) research agenda is well recognized, we consistently have been one of the top 3 sites for enrolling patients into studies open to all sites. Our history of retention of youth in care (88-96%) and in all research protocols-behavioral, therapeutic and community-based (average of 89%) during ATN II, highlights our capacity for continued work with the ATN. The Stroger/CORE ATU employs well-characterized outreach techniques to identify youth and engage them in care including: targeted, social networking and marketing;a community-based outreach program and drawing youth from our HIV specific and general adolescent clinics. RELEVANCE: The ATN research agenda in Chicago is relevant to the public health issues faced by youth in our community. An understanding of how and among whom the virus is transmitted, learning what issues face adolescents as they enter care or not, or adhere to medication regimens or not, is crucial in the fight against HIV/AIDS. ATN research studies provide much needed evidenced-based strategies to develop public health policies and programs to aid in the reduction of HIV/AIDS and co-morbidities among adolescents.